The measurement of the Hall angle of semiconductor material is an important aspect of its electrical characterization. The sign of the Hall angle indicates whether material is p-type or n-type while the magnitude of the Hall angle is proportional to the majority carrier mobility. However, prior Hall effect measurement requires some sort of contacting arrangement and/or special sample geometry and are therefore damaging or at least contaminating in nature. Thus, a noncontacting measurement of Hall angle is desirable.
A noncontacting method for the measurement of Hall mobility in semiconductor materials is described by Nyberg et al. in the Canadian Journal of Physics 40, (1962) November 1974. In this method a circular electrical current is inductively coupled into a spherical or cylindrical sample of semiconductor material. An imposed d-c magnetic field then produces a rotation of the plane of the inductively coupled current which is detected as a signal related to the Hall mobility. However, Nyberg described this technique as being sensitive to the precise relative position of the pickup coil and the sample, and, as disclosed, it is not applicable to the technologically important wafer sample geometry.